Amine, alcohol and emulsifier corrosion inhibiting composition and process



3,088,796 AMINE, ALCOHOL AND EMULSH ER CORROSION INITING COIVEFOSITIONAND PROCESS Harry Lewis Kahler, Feasterville, and-James Kenneth Brown,Huntingdon Valley, Pa., assignors to Betz Laboratories, Inc,Philadelphia, Pa., a corporation of Pennsylvania No Drawing. Filed Dec.14, 1960, Ser. No. 83,128 21 Claims. (Cl. 212.7)

The present invention relates to processes of inhibiting corrosion andpreventing degradation of corrosion inhibitors, and tocorrosion-inhibiting compositions.

A purpose of the invention is to minimize fouling of equipment bycorrosion-inhibiting compositions.

A further purpose is to eliminate or minimize the corrosion of chemicalfeed lines used to feed corrosion inhibitors.

A further purpose is to increase the stability of corrosion-inhibitingcompositions.

Further purposes appear in the specification and in the claims.

Film-forming primary aliphatic amines, having straight carbon chains inthe range between 14 and 29 carbon atoms, have proven to be veryeffective as corrosion inhibitors in steam lines, condensate lines andequipment used in steam and condensate systems where an aqueous liquidor vapor is in flow. See Kahler US. Patent No. 2,460,259, grantedJanuary 25, 1949; Maguire US. Patent No. 2,712,531, granted July 5,1955; and Gunderson U.S. Patent No. 2,767,106, granted October 16, 1956.

These primary aliphatic amines have been shown to undergo structuralchange they are fed by any of the usual methods, for example as amineacetate, amine glycollate, or the like. These structural changes producedeposits which foul the equipment, increasing the downtime anddecreasing the corrosion protection, since the products resulting fromsuch structural changes are not corrosion inhibitors. The productsproduced by the degradation vary in composition, depending on whetherpolymerization, hydrolysis or some other chemical change takes place.

ELIMINATION OF LOWER FATTY ACID FOR DIS- PERSINGHHE AMINESUSE OF ALCOHOLAND USE OF EMULSlFIERS A second and equally serious problem which hasbeen encountered in the commercial application of aliphatic amines isthe problem of forming suitable chemical feed dispersions. These aminesare waxy and insoluble in water, and they form poor dispersions in waterfor feeding to steam and condensate lines and systems. The acetate orglycollate salts of the amines are soluble in water and are readilydispersible. The amine acetate, mixtures of the amine acetate and theamine, the mixtures of the amine glycollate and the amine and mixturesof acetic acid or glycollic acid and the amine have been used to producecolloidally dispersed feeding compositions. While it is possible by suchdispersions to feed the amine, these dispersions involve certaindisadvantages.

It has been found that the concentrated amine acetate or glycollate ormixtures thereof undergo structural changes or degradation more readilythan the" amine itself. Furthermore, the amine acetate or glycollate ormixtures of the amine and the amine acetate or glycollate inconminimizing corrosion of the chemical feed' line.

3,038,796 Patented May 7, 1963 ice centrated. form corrode the'chemicalfeed line at points of marked temperature increase Where the chemicalfeed line enters thesteam system. The cold chemical feed dispersion, asit nears the hot steam line, increases markedly in temperature. As aresult of the increase in temperature, the amine acetate or, glycollateor mixtures of the amine acetate and the amine, or mixtures of the amineglycollate and the amine produce free acetic or glycollate acid asfollows:

The free acetic acid or. glycollic acid thus formed corrodes thechemical feed line at the point of temperature increase. When thechemical feed dispersion reaches the main steam line and is diluted bythe steam to the low concentration which is used in the steam line, thelow concentration of acetic acid or glycollic acid present is no longerhigh enough to produce this undesirable corrosion, and the steam andcondensate lines are thus adequately protected by the film-forming aminewhich is present.

The present invention is concerned particularly with minimizing oreliminating the fouling from structural changes of the film-formingamine, and eliminating or As a result, it is possible under the presentinvention to obtain greater protection in the steam or condensate linead in metallic equipment which contacts the steam or the con densate.

CORROSION TESTS AT FEEDING CONCENTRATIONS Table 1 submitted herewithshows the results of comparati ve tests under conditions which simulatedthe conditions in a steam boiler feed line as to temperature andpressure. The temperature used was 400 F. and the pressure was 262p.s.i. The products were dissolved in distilled water and exposed for 20hours at this temperature and pressure in contact with low carbon (A1311010) steel corrosion specimens.

The conditions of'test in Table 1 are comparable to those at the pointwhere the feed line enters the steam header of a boiler where corrosionof the feed line most frequently occurs.

The results in Table 1 show that water done and the film-forming aminealone were substantially non-corrosive. Acetic acid and glycollic acidare very corrosive, exceeding 900 mils per year average penetration. Thecorrosion by these acids was greatly reduced when the amine was presentin feed concentrations, but the rate was still too high to be toleratedunder satisfactory operating conditions. All of the alcohols and theemulsifiers alone and together were substantially completelynon-corrosive, and behaved in this manner whether or not the amines werepresent. Thus, any combination of the amines, alcohols and emulsifierstested indicated that the combination Was just as non-corrosive as theamines alone. It, therefore, is evident that feed line corrosion can besolved if lower fatty acids, having a carbon chain length of 4 or less,are eliminated, and if a combination of amine and proper emulsifier, oramine, alcohol and proper emulsifier can be used. This not only solvesthe problem, but it also provides an amine in end-use concentrationwhich is more stable than the amine-acid series.

We find that the aliphatic alcohols having from 1 to 6 carbon atoms inthe carbon chain and from 1 to 6 hydroxyl groups are most desirable,although very low alcohols like methyl, ethyl and isopropyl areundesirable for practical reasons because of toxicity, odor and lowflash point. Dihydric alcohols like propylene glycol and diethyleneglycol are very advantageous in promoting good product quality andfeeding, and they have high flash points so that they do not present afire hazard.

Higher polyhydric alcohols such as glycol, glycerol, sorbitol ndpentaerythritol are also satisfactory.

The most satisfactory film-forming amines according to our tests areoctadecylamine (C docosylamine (behenylamine) (C and a mixture of aminescomposed of 25% of docosylamine (C 30% of eicosylamine (C 30% ofoctadecylamine (C 13% of hexadecylamine (C and 2% of tetradecylamine (Cthe percentages being by weight. This mixture is referred to as aminemixture.

Extensive tests were made with a wide variety of emulsifiers includingpolyoxyethylene ethers, polyoxyethylene acids, polyoxyethylene esters,polyoxyethylene alcohols, polyoxyethylene nitrogen-bearing compounds,sulphonated compounds, sulphated compounds, fatty esters, assortednitrogen compounds, fats and the like.

It is important to stress that the emulsifier must solve two problems.First of all, it must provide from the amine or amine alcoholcombinations a sufficiently good product quality for practical use inthe absence of a lower fatty acid, and second it must give morestability to the amine in the end use, due to the elimination of thelower fatty acid.

NOMENCLATURE Very excellent results were obtained with an amine salt asshown in the following formula:

(0 Hz OHzO) yH Formula I where R is a residue of a fatty acid having acarbon chain length of 10 to 29 and preferably 10 to 24 inclusive, mostdesirably 10 to 18 inclusive, such as a cocoanut acid residue containingC C and C mixed fatty acid residues, an oleyl residue, or a stearylresidue and X and Y total the mol ratio of polyoxyethylene to R in themolecule and involve a mol ratio of total polyoxyethylene to R ofbetween 2:1 and 15:1. R can be saturated or can contain one double bondin the carbon chain.

These materials are commonly referred to as Ethoquads, and aredesignated by an initial letter or number, a slant line and a finalnumber. The initial letter or number designates the aliphatic group orgroups which compose R as follows:

C==cocoanut acid residue, consisting of C C and C mixed O=oleyl residue18=stearyl residue The number to the right of the slant line is thetotal of X+Y10 so that Ethoquad 18/25 is of the stearyl series and has amol ratio of C H O to R of 15:1.

Typical examples of the Ethoquads are as follows:

Ethoquad C/ l 2 Ethoquad C/ 25 Ethoquad 0/12 Ethoquad O/ 15 Ethoquad0/25 Ethoquad 18/ 12 Ethoquad 18/15 Ethoquad 18/25 It has been founddesirable in some cases to use a fur- A ther polyoxyethylene aminocompound which has a formula as follows:

oniongonn 01120112051! Formula II where R is a fatty acid residue havinga carbon chain length of 10 to 30 and preferably 10 to 24, and the molratio of polyoxyethylene to R is as follows:

C series-cocoanut acids, C C and C ratio of polyoxyethylene to R variesfrom 2:1 to 15: 1.

S series-soya acids, C to C with some oleic, ratio of polyoxyethylene toR varies from 2:1 to 15:1.

T series-tallow acids, C to C containing some oleic, ratio ofpolyoxyethylene to R varies from 2:1 to 5:1.

18 series-stearic acid, C ratio of polyoxyethylene to R varies from 2:1to 50:1.

0 series-oleic acid, C with one double bond, ratio of polyoxyethylene toR varies from 2:1 to 5: 1.

In this case also X-l-Y is the ratio of polyoxyethylene to R in themolecule.

Other values of X+Y for other fatty acids are obtained by interpolation.

These compounds are usually called Ethomeens followed by a letter ornumber, a slant line and a second number. The first letter or numberindicates the nature of the group R and the second letter or numberminus 10 indicates the total of X-i-Y, as follows:

Ethomeen C/ 12 Ethomeen C/l5 Ethomeen C/20 Ethomeen C/25 Ethomeen S/l2Ethomeen S/ 15 Ethomeen S/20 Ethomeen S/25 Ethomeen 18/12 Ethomeen 18/15 Ethomeen =18/60 Ethomeen O/ 12 Ethomeen O/15 THE INVENTION It hasbeen discovered according to the present invention that extremelyeffective, smooth, stable dispersions can be made of filming amines asabove described by utilizing one of the materials of Formula I as adispersing agent. In the concentrated solution which is to 'be marketed,the filming amine will desirably make up to 30% by weight. The lowerlimit of the quantity of amine will be sufiicient to form a film on thesurfaces, which will ordinarily be 0.1% amine by weight. In the steam orwater after feeding the filming amine will have a concentration up to 10p.p.m. and preferably up to 5 p.p.m. The lower limit of the quantity ofamine will be sulficient to form a film on the surfaces, which willordinarily be 0.1 p.p.m.

The compound of Formula I used as an emulsifier will have aconcentration in the concentrated solution which is fed in the range upto 10% by weight and preferably up to 5% by weight. The lower limit willinvolve suflicient compound of Formula I to convey the filming amine tothe surfaces, usually 0.1% 'by weight. In the steam or water afterdilution the compound of Formula I will have a concentration in therange up to 10 p.p.m., preferably up to 5 p.p.m. and most desirably upto 3 p.p.m. The lower limit will involve suflicient compound of FormulaI to convey the filming amine to the surface, usually 0.1 p.p.m.

In order to produce the best results, an alcohol of the class consistingof primary and secondary aliphatic alcohols having a carbon chain lengthbetween 1 and :weight.

6 and having between 1 and 6 hydroxyl groups should be employed with thefilming amine and with the emulsi; tier of Formula I. The alcohol willpreferably be saturated. For this purpose the preferred concentration inthe concentrated solution which is to be fed should be up to andpreferably up to, 5% by weight The lower limit will involve sufiicieutalcohol to convey the filming amine to the surface, usually 0.1%. byweight. The concentration of the alcohol in the steam or water afterdilution should be in the range up to. 5 p.p.m. and most desirably up to3 p.p.m. The lower limit will in- "volve sufficient alcohol to conveythe filming amine to the surface, usually 0.1 p.p.m.

For best results with the lowest concentration of emulsifier, it is verydesirable to use the emulsifier'of Formula II as a second emulsifier,preferably with the aliphatic alcohol. In this case the concentration ofthe emulsifierof Formula II in the concentrated dispersion which is fedwill preferably be in the range up to 10% by weight and most desirablyup to 5% by weight. The lower limit will involve sufiicient compound ofFormula. II to convey the filming amine to the surface, usually 0.1% byweight. In the dilute steam or water after feeding, the concentration ofemulsifier according to Formula II will be up to 10 p.p.m. andpreferably up to 5. p.p.m. and most desirably up to 3 p.p.m. The lowerlimit will involve sufiicient compound of Formula II to convey thefilming amine to the surface, usually 0.1 p.p.m.

The most powerful emulsifiers are those conforming to Formula I. Thecompounds of- Formula II are of lesser power but cooperate in anassisting role.

As will be evident from Table 2, which illustrates the abilities of thevarious emulsifiers to maintain stable emulsions in the concentratedemulsion and in the 5% feed solution (5% product, 95% water by weight),Ethoquad 18/25 was powerful enough to emulsif'y a 6% by weightoctadecylamine dispersion at concentrations as low as 1% by weight, andat the same time produced verygood feeding solutions. Even withconcentrations of Ethoquad 18/25 as low as 0.3% by weight in theconcentrated dispersion, the product quality was good but the feed in 5%by weight solution was not successful.

It will be evident from Table 2 that the use of an emulsifier of FormulaI with an emulsifier of Formula II conjointly, for example Ethoquad 18/25 and Ethomeen 18/12, was highly desirable. The presence of Ethomeen18/ 12 made an unsuccessful octadecylamine-Ethoquad product and feedinto a successful one. The Ethomeen failed to fully recoup the qualityof the product at concentrations of 0.05%, 0.1% and 0.2% by weightEthoquad in the concentrated dispersion, but at concentrations of 0.3%by weight in the concentrated dispersion good feeds were obtained whichEthoquad alone failed to accomplish even with concentrations of 0.5% byweight.

It was particularly noticeable that the use of a compound of Formula Iwith a compound of Formula II was particularly attractive because theEthomeen added body and smoothness to the mix.

At upper levels to Ethoquadup to 3% by weight, the combination withEthomeen gave excellent products and excellent feeds which werecompletely stable for long periods of time. This was an outstandingfeature of these emulsified products as compared with the amine-acetateand amine-glycollate series. The advantage of the products of theinvention was evident in feeds and in product stability.

It was found that combinations with Ethomeen and an alcohol such asdiethylene glycol made unsuccessful amine-Ethoquad products and feedsinto successful ones as is shown in Table 3. For example, the 6% byweight amine-Ethoquad combination was not successful either as a mix, oras a feed where Ethoquad was under 0.5% by Where Ethomeen 18/ 12 anddiethylene glycol were successively at levels of 0.5%, 1.5% and 2.5% byweight, mixes of 6% by weight ofamine respectively with 0.1%, 0.2% and0.3% of Ethoquad were turned into successful products and feedingsolutions. At higher levels of Ethoquad, the Ethomeen and diethyleneglycol did no harm, and imparted smoothness and produced very stablemixes and feeds. Tests 83 to 88 indicate that various mixtures of amineto Ethoquad, to Ethomeen, to diethylene glycol were possible indicatingthe flexibility in combining these materials.

A relationship exists between the components of these products. Therelationship is a complex one as it depends on many features includingthe concentration of amine, the ratio of amine to emulsifier, such asamine to Ethoquad, and the ratio of amine to emulsifier to secondemulsifier to alcohol, such as amine to Ethoquad, to Ethomeen, todiethylene glycol. As a result of hundreds of compositions made, theranges set forth above have been determined.

The use of the two emulsifiers accomplished what one emulsifier wasunable to do and the use of the two emulsifiers with the alcohol madepoor products into good ones as shown in Table 3. The problem is furthercomplicated as the ratios depend upon the power of the emulsifiers andthe solvent action of the alcohols.

Emulsifiers and alcohols of the invention hold up to 30% by weight aminecomposition in water with additions of up to 20% of emulsifier,providing good product quality and feed.

Emulsifying power is somewhat dependent on the relative hydrophilic andhydrophobic balance. Thus, the Ethoquads of the stearyl series having aratio of polyoxyethylene to R from 2:1 to 15:1 were excellent. Ethoquadsof the oleyl series with an unsaturated carbon chain length of 18 and ofthe cocoanut series were also satisfactory.

Ethomeens of the stearyl series having a carbon chain length of 18,ranging from 18/25 to 18/60 were satisfactory over a range ofpolyoxyethylene to R ratios of 2:1 to 50:1. Ethomeens of the cocoanutseries with a carbon chain length of 10:14, of the soy bean serieshaving a carbon chain length of 16:18 with some oleyl, and Ethomeens ofthe tallow series having a carbon chain length between 16 and 18 andthose of the oleyl series having a carbon chain length of 18 weresatisfactory but required slightly higher concentrations for a givenamine level.

It has been found that emulsifying and dispersing these C to C amines byemulsifiers and alcohols according to the invention in no way sacrificescorrosion protection in the end use concentrations. In fact, eliminatingthe lower fatty acids lowered the degradation of the amine actuallywhile retaining the corrosion protection. Table 4 shows that theemulsifiers and alcohols do not lower the corrosion protection affordedby the amines alone. These results were obtained in the laboratory andsome of the combinations have been verified in plant practice.

The following compositions show some typical alcohols and emulsifiersand the flexible ratios that are possible. These all had good productquality, and gave good feeding solutions on dilution with water. Thepercentages are by weight.

Composition 1.-6% octadecylamine, 2% propylene glycol, 1% Ethoquad 18/25and 91% water.

Composition 2.6% octadecylamine, 10% propylene glycol, 10% Ethoquad18/25, and 74% Water.

Composition 3.6% amine mixture, 2% diethylene glycol, 1% Ethomeen 18/20and 91% water.

Composition 4.-6% amine mixture, 10% isopropyl alcohol, 2% Ethomeen 18/20 and 82% water.

Composition 5.3% octadecylamine, 15% propylene glycol, 2% Ethoquad 18/25and water.

Composition 6.-2% amine mixture, 2% propylene glycol, 6% Ethomeen 18/12,1% Ethoquad 18/25 and 89% water.

Composition 7.30% amine mixture, propylene glycol, 10% Ethoquad 18/25and 50% water.

Composition 8.6% octadecylamine, diethylene glycol, 2% Ethoquad C/ 15,and 90% water.

Composition 9.6% octadecylamine, 2% glycerol, 1% Ethoquad 18/25 and 91%water.

Composition 10.10% amine mixture, 5% Ethoquad 18/25, 10% diethyleneglycol and 75% water.

Composition 11.6% amine mixture, 2% sorbitol, 1% Ethoquad 18/25 and 91%water.

Composition 12.-3% amine mixture, 4% Ethomeen C/ 25, 1 Ethoquad 18/25,92% water.

Composition 13.3% amine mixture, 4% Ethomeen S/l2, 1% Ethoquad 18/25,92% water.

Composition 14.-3% amine mixture, 4% Ethomeen 18/12, 1% Ethoquad C/l5,92% Water.

Composition 15.3% amine mixture, 4% Ethomeen O/12, 1% Ethoquad 18/25,92% water.

Composition 16.3% amine mixture, 4% Ethomeen T/12, 1% Ethoquad 18/25,92% water.

Composition 17.6% amine mixture, 2% Ethoquad 18/25, 2% Ethomeen C/15,90% water.

Composition 18.6% amine mixture, 2% Ethoquad 18/25, 2% Ethomeen 0/12,90% water.

Composition 19.6% amine mixture, 2% Ethoquad 18/25, 2% Ethomeen T/12,90% water.

Composition 20.6% amine mixture, 2% Ethoquad 18/25, 2% Ethomeen 8/20,90% water.

Composition 2l.6% amine mixture, 2% Ethoquad 0/12, 92% water.

Composition 22.6% amine mixture, 2% Ethoquad C/12, 92% water.

Composition 23.-6% amine mixture, 2% Ethoquad O/12, 2% Ethomeen T/12,90% water.

Composition 24.6% amine mixture, 2% Ethoquad C/ 12, 2% Ethomeen S/ 20,90% Water.

Composition 25.6% amine mixture, 2% Ethoquad O/15, 2% Ethomeen C/15, 90%water.

Composition 26.6% amine mixture, 2% Ethoquad C/25, 2% Ethomeen O/l2, 90%Water.

In view of our invention and disclosure, variations and modifications tomeet individual whim or particular need will doubtless become evident toothers skilled in the art to obtain all or part of the benefits of ourinvention without copying the process and composition shown, and we,therefore, claim all such insofar as they fall within the reasonablespirit and scope of our claims.

Table I CORROSION TEST AT FEEDING CONCENTRATIONS Weight, percent Weightpercent Other Ingredients Steel Ave. P, Milsl- Year Amine Distilledwater 9 1% acetic acid 0.8 glycollic acid 1% acetic acid 0.8 glycollicacid.

2Ethoquad 18/25- 0.2 Ethoquad 18/25 2 Ethomeen 18/12, 0.2 1 Ethoquad18/25. 6 propylene glycol 3 1 2 propylene glycol,

Ethoquad 18/25.

2 propylene glycol, Ethoquad 18/25, Ethomelen 18/12. I

5 propyene gyco,

Ethoquad 18/25.

6 dlethylene glycol 1 diethylene glycol 2 propylene glycol, 1

Etlioquad 18/25.

2 propylene glycol, 6 Ethomeen 18/12, 1 Ethoquad 18/25.

Amine Mixture--. 2

Hanr l Composltionl. 1 Composition 6.

Table2 Weight Weight Weight Product 5% Feed Number Percent PercentPercent Quality Solution Amine Ethoquad Ethomeen of Mix Mixture 18/2518/12 6 0.05 6 0.1 6 0.2 6 0.3 6 0.5 6 1 6 3 6 0.05 l 6 0.05 3 6 0.05 5D 6 0.1 1 6 0.1 3 6 0.1 5 6 0.2 1 6 0.2 3 6 0.2 5 6 0.3 1 6 0.3 3 -doDo. 6 0.3 5 .do Do. 6 0.5 1 Good--- Do. 6 0.5 3 do Do. 6 0.5 5 do Do. 61 1 do. Do. 6 1 3 do Do. 6 1 5 do Do. 6 3 2 do Do. 6 3 5 .do Do. 6 3 8do- Do. 3 1 3 do Do. 5 2 5 .do Do. 2 1 2 do. Do. 10 3 10 do Do. 10 5 10.do Do. 3 4 3 do Do.

Table3 Weight Weight Wieght Weight Product Num- Percent Percent PercentPercent Quality 5% Feed ber Amine Ethoquad Ethomeen Diethyl- MixSolution Mixture 18/25 18/12 ene Glycol Test Conditions: lwo daydifierential tests on high carbon steel exposed to water havingcomposition of: ppm. 002 and 0.1 p.p.m. 03 at 150-160 F. Flow rate pastthe specimen was 0.03 it. per second.

Having thus described our invention what we claim as new and desire tosecure by Letters Patent is:

1. The process of protecting metal surfaces against corrosion by afiowing stream of a member of the group consisting of corrosive aqueousliquid and vapor, which comprises adding to such flowing stream adispersion of a film-forming aliphatic primary amine having between 14and 29 carbon atoms in the carbon chain and an emulsifier according tothe following formula:

where R is a residue of fatty acid having a carbon chain length of 10 to29, and x and y total the mol ratio of polyoxyethylene to R in themolecule and involve a mol ratio of total polyoxyethylene to R ofbetween :1 and 15:1.

2. The process of claim 1, in which the amine is octadecylamine and theemulsifier referred to in claim 1 is a stearyl amine salt having a molratio of polyoxyethylene to R of 15 :1.

3. The process of claim 1, in which the amine is 'behenylamine and theemulsifier referred to in claim 1 is a stearyl amine salt having 9, molratio of polyoxyethylene to R of 15:1.

4. The process of claim 1, in which the amine is octadecylamine, theemulsifier of the formula referred to in claim 1 has R which is stearyland has a mol ratio of polyoxyethylene to R of 15:1, which comprisesadding to the liquid or vapor a second emulsifier according to thefollowing formula:

(0H2oHlo),H

Hzc im H in which R is stearyl and the mol ratio of polyoxyethylene to Ris 2:1.

5. The process of claim 1, in which the amine is behenylamine and in theformula referred to in claim 1, R is stearyl having a mol ratio ofpolyoxyethylene to R of 15:1, which comprises adding to the liquid orvapor a second emulsifier according to the following formula:

(CHiGI-Izo),11

in which R is stearyl, and which has a mol ratio of polyoxyethylene to Rof 2:1.

6. The process of claim 1, having a concentration of aliphatic primaryamine between an effective amount and p.p.m., and having a concentrationof the emulsifier referred to in claim 1 of between an effective amountand 3 ppm.

7. The process of claim 1, which further comprises adding to the liquidor vapor an alcohol of the class consisting of primary and secondarypolyhydric aliphatic alcohols having a carbon chain length between 2 and6 and having between 2 and 6 hydroxyl groups.

8. The process of claim 7, in which the amine is octadecylamine, thealcohol is propylene glycol, the emulsifier according to the formulapreviously referred to is a stearyl amine salt having a mol ratio ofpolyoxyethylene to R of :1, which comprises adding to the liquid orvapor a second emulsifier according to the following formula:

9. The process of claim 7, in which the amine is behenylamine, thealcohol is propylene glycol, the emulsifier of the formula abovereferred to is a stearyl amine salt having a mol ratio ofpolyoxyethylene to R of 15:1, which comprises adding to the liquid orvapor a second emulsifier having the following formula:

(OH CHrOhH (CHzCH20)yH in which R is stearyl and which has a mol ratioof polyoxyethylene to R of 2:1.

10. The process of claim 7, in which the concentration of aliphaticprimary amine is between an effective amount and 10 p.p.m., theconcentration of the alcohol is between an effective amount and 5 ppm.and the concentration of the emulsifier of the formula above referred tois between an effective amount and 5 ppm.

11. The process of claim 7, which comprises further adding to the liquidor vapor a second emulsifier according to the following formula:

(CHzCHrOhH (CHzCH20) H where R is a fatty acid residue having a carbonchain length of 10 to 30.

12. The process of claim 11, in which the concentration of primaryaliphatic amine is between an effective amount and 10 p.p.m., theconcentration of the emulsifier referred to in claim 1 is between aneffective amount and 5 p.p.m. and the concentration of the emulsifierreferred to in claim 11 is between an effective amount and- 5 p.p.m.

13. The process of claim 1, which comprises adding to the liquid orvapor a second emulsifier having the following formula:

(CHzCHzO) XE H2CH2O)y where R is a fatty acid residue having a carbonchain length of 10 to 30.

14. The process of claim 13, in which the concentration of primaryaliphatic amine is between an effective amount and 10 p.p.m., theconcentration of alcohol is between an effective amount and 5 ppm. andthe concentration of the compound referred to in claim 1 is between aneffective amount and 5 ppm. and the concentration of the compoundreferred to in claim 13 is between an effective amount and 5 ppm.

15. The process of reducing degradation of film-forming aliphaticprimary amines having from 14 to 29 carbon atoms in the carbon chain,which comprises dis-- persing said amine in a water based dispersion bya dispersing agent according to the following formula:

-(onlomomr where R is a residue of a fatty acid having a carbon chainlength of 10 to 29, and x and y total the mol ratio of polyoxyethyleneto R of between 5:1 and 15 :1, while maintaining the dispersion freefrom fatty acid having a carbon chain length of 4 carbon atoms or below.

16. The process of claim 15, which comprises dispersing the film-formingaliphatic primary amine in the presence of an aliphatic alcohol of theclass consisting of primary and secondary polyhydric aliphatic alcoholshaving a carbon chain length between 2 and 6 and having between 2 and 6hydroxyl groups.

17. The process of claim 15, which comprises further adding a secondemulsifier having the following formula:

(CHzC Hz 0) 11 HiCEhO) yH where R is a residue of a fatty acid having acarbon chain length of 10 to 29, and x and y total the mol ratio ofpolyoxyethylene to R in the molecule and involve a mol ratio ofpolyoxyethylene to R of between :1 and 15:1, and up to of an alcohol ofthe class consisting of primary and secondary polyhydric aliphaticalcohols having a carbon chain length between 2 and 6 and having between2 and 6 hydroxyl groups, there being an effective amount of eachemulsifier.

19. A composition of claim 18, which also contains up to 10% of a secondemulsifier according to the following formula:

(CH2CH20)yH where R' is a fatty acid residue having a carbon chainlength of 10 to 30, there being an eifective amount present.

20. A composition of claim 19, in which the filmforming amine has acarbon chain length between 18 12 and 22, the emulsifier referred to inclaim 18 has R which is stearyl and has a mol ratio of polyoxyethyleneto R of 15:1, and the second emulsifier referred to in claim 19 has Rwhich is stearyl and has a mol ratio of polyoxyethylene to R of 2:1 andin which the alcohol is diethylene glycol.

21. A composition essentially composed of up to 30% by Weight of afilm-forming amine of a class consisting of octadecylamine andbehenylamine, up to 10% by weight of a compound of the followingformula:

in which R is stearyl and x and y total the mol ratio of polyoxyethyleneto R in the molecule, which mol ratio is 15:1, up to 10% by weight of anemulsifier having the following formula:

omonzo X11 It-N onlorno) YE in which R is stearyl and the mol ratio ofpolyoxyethylene to R is 2:1, balance water, there being an effectivequantity of each emulsifier.

References Cited in the file of this patent UNITED STATES PATENTS2,759,975 Chiddix et a1. Aug. 21, 1956 2,878,155 Cruickshank Mar. 17,1959' 2,956,889 Denman Oct. 18, 1960

1. THE PROCESS OF PROTECTING METAL SURFACES AGAINST CORROSION BY AFLOWING STREAM OF A MEMBER OF THE GROUP CONSISTING OF CORROSIVE AQUEOUSLIQUID AND VAPOR, WHICH COMPRISES ADDING TO SUCH FLOWING STREAM ADISPERSION OF A FILM-FORMING ALIPHATIC PRIMARY AMINE HAVING BETWEEN 14AND 29 CARBON ATOMS IN THE CARBON CHAIN AND AN EMULSIFIER ACCORDING TOTHE FOLLOWING FORMULA: